Abstract
In query optimization, a given query will be transformed by rewrite rules into an equivalent execution plan that is cheaper than the straightforwardly assigned plan according to some cost model. Finding the cheapest of all equivalent execution plans is a challenge since the rewriting of complex queries on the basis of a large set of rewriting rules may potentially span a very large space of equivalent plans. Consequently, one has to either use search strategies to explore (parts of) the search space or some heuristics to prune this space thus making it efficiently traversable.
This paper presents the use of search strategies in the CROQUE project. The adaptation of some common strategies led to the development of a simple but powerful heuristics which is demonstrated by examples executed in the CROQUE prototype. The proposed heuristics can support any random-based search strategy or can be used stand-alone. It may be integrated seamlessly into most of the present query optimizers without almost any effort.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
R.G.G. Cattell, editor. The Object Database Standard: ODMG-93, Release 1.2. Morgan-Kaufmann, San Mateo, CA, 1996.
L. Fegaras, D. Maier, and T. Sheard. Specifying Rule-based Query Optimizers in a Reflective Framework. In Proc. of the 3rd Int. Conference on Deductive and Object-Oriented Databases, pages 146–168, New York, December 1993. Springer.
G. Graefe and D.J. DeWitt. The EXODUS Optimizer Generator. In Proc. of the ACM SIGMOD Int. Conference on Management of Data, pages 160–172, San Francisco, CA, USA, May 1987.
D. Gluche, T. Grust, C. Mainberger, and M.H. Scholl. Incremental Updates for Materialized Views with User-Defined Functions. In Proc. of the Fifth Int. Conference on Deductive and Object-Oriented Databases (DOOD‘97), Montreux, Switzerland, LNCS 1341, Springer, pages 52–66, December 1997.
T. Grust, J. Kröger, D. Gluche, A. Heuer, and M.H. Scholl. Query Evaluation in CROQUE — Calculus and Algebra Coincide. In Proc. of the 15th British National Conference on Databases (BNCOD 15), London, UK, LNCS 1271, Springer, pages 84–100, July 1997.
G. Graefe and W.J. McKenna. The Volcano Optimizer Generator: Extensibility and Efficient Search. In IEEE Conference on Data Engineering 4/1993, pages 209–218, Vienna, Austria, April 1993.
G. Graefe. The Cascades Framework for Query Optimization. Bulletin of the Technical Committee on Data Engineering, 18(3):19–29, September 1995.
A. Heuer and J. Kröger. Query Optimization in the CROQUE Project. In Proc. of the 7th Int. Conference on Database and Expert Systems Applications (DEXA‘96), Zurich, Switzerland, LNCS 1134, Springer, pages 489–499, September 1996.
J. Hook and T. Sheard. A Semantics of Compile-time Reflection. Technical report, Oregon Graduate Institute, Portland, Oregon, 1993.
R. Illner. Employment of Simulated Annealing for a Cost-Based Optimization of Object-Oriented Queries. Master’s thesis, CS Dept., University of Rostock, June 1996. In german.
Y. Ioannidis and V. Poosala. Histogram-Based Solutions to Diverse Database Estimation Problems. Bulletin of the Technical Committee on Data Engineering, 18(3):10–18, September 1995.
Y.E. Ioannidis and E. Wong. Query Optimization by Simulated Annealing. In Proc. of the 13th ACM SIGMOD Int. Conference on Management of Data, pages 9–22, San Francisco, CA, USA, May 1987.
Y.C. Kang. Randomized Algorithms for Query Optimization. PhD thesis, University of Wisconsin, Madison, October 1991.
J. Kröger, R. Illner, S. Rost, and A. Heuer. Query Rewriting and Search in CROQUE. Preprint CS-15-98, CS Dept., University of Rostock, December 1998. URL: http://wwwdb.informatik.uni-rostock.de/~jo/CS-15-98.html.
A. Kemper and G. Moerkotte. Query Optimization in Object Bases: Exploiting Relational Techniques. In J.C. Freytag, D. Maier, and G. Vossen, editors, Query Processing for Advanced Database Systems, chapter 3, pages 63–98. Morgan Kaufmann Publishers, 1994.
J. Kröger, S. Paul, and A. Heuer. On the Ordering of Rewrite Rules. In Proc. of the Second East-European Symposium on Advances in Databases and Information Systems (ADBIS’98), Poznan, Poland, LNCS 1475, Springer, September 1998.
J. Kröger, S. Paul, and A. Heuer. Query Optimization: Ordering Rules? Preprint CS-12-98, CS Dept., University of Rostock, June 1998. URL: http://wwwdb.informatik.uni-rostock.de/~jo/CS-12-98.html.
F. Ozcan, S. Nural, P. Koksal, M. Altinel, and A. Dogac. A Region Based Query Optimizer Through Cascades Query Optimizer Framework. Bulletin of the Technical Committee on Data Engineering, 18(3):30–40, September 1995.
L.C. Paulson. ML for the Working Programmer. Cambridge University Press, 2nd edition, 1996.
J. Robinson and B. Lowden. Semantic Query Optimisation and Rule Graphs. In Proc. of the 5th KRDB Workshop, Seattle, WA, May 1998.
S. Rost. Analysis of Alternative Search Strategies for a Cost-Based Optimization of Object-Oriented Queries. Master’s thesis, CS Dept., University of Rostock, June 1996. In german.
H. Riedel and M.H. Scholl. A Formalization of ODMG Queries. In Proc. of the 7th Int. Conference on Database Semantics (DS-7), October 1997.
T. Sheard. Guide to using CRML–Compile-Time Reflective ML. Technical report, Pacific Software Research Center, Oregon Graduate Institute of Science & Technology, Beaverton, Oregon, October 1993.
Michael Steinbrunn, Guido Moerkotte, and Alfons Kemper. Optimizing Join Orders. Technical Report MIP-9307, Faculty of mathematics and computer sciences, University of Passau, 1993.
M. Srinivas and L.M. Patnaik. Genetic Search: Analysis Using Fitness Moments. IEEE Transaction on Knowledge and Data Engineering, 8(1):120–133, Feb. 1996.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1999 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Kröger, J., Illner, R., Rost, S., Heuer, A. (1999). Query Rewriting and Search in CROQUE. In: Eder, J., Rozman, I., Welzer, T. (eds) Advances in Databases and Information Systems. ADBIS 1999. Lecture Notes in Computer Science, vol 1691. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-48252-0_22
Download citation
DOI: https://doi.org/10.1007/3-540-48252-0_22
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-66485-7
Online ISBN: 978-3-540-48252-9
eBook Packages: Springer Book Archive